1. Field of the Invention
This invention relates generally to remotely-controlled unmanned mobile devices adapted to function as a robot scout to gather information regarding conditions prevailing at a disaster site and to communicate this information to a rescue mission.
2. Status of Prior Art
In disaster situations, the availability of timely and accurate information regarding conditions prevailing at the site of the disaster may be crucial to the success of a rescue mission. Typical, yet not exclusive, of such situations are an explosion at a chemical manufacturing facility, the leakage of hazardous materials at an urban site, a nuclear reactor accident or an earthquake as well as other serious ecological and natural catastrophes.
Should a rescue mission seek to gain advance information regarding conditions prevailing in the region of a disaster so that the mission can decide on appropriate rescue procedures, in many cases this attempt may expose scouts assigned to this task to life-threatening risks. For example, if the disaster area is the site of a nuclear reactor accident in which released into the area are lethal radioactive particles, scouts would be ill advised to enter this area.
The present invention resides in a remotely-controlled unmanned mobile device (UMD) functioning as a robot scout adapted to enter and reconnoiter a disaster site in behalf of a rescue mission to gather information in regard to conditions prevailing at the site and to communicate this information to the mission. The UMD is operable either in an air-mobility mode or in a ground-mobility mode, so that it is capable of fully exploring the site. While conditions prevailing at the site of a disaster may threaten the life of a living scout, they can do no injury to a robot scout.
Because in its air-mobility mode the UMD operates in a manner similar to that of a vertical take-off and landing vehicle (VTOL), of prior art interest in this regard is the unmanned VTOL air vehicle described e.g. in U.S. Pat. No. 5,295,643 to Ebbert et al. This device is capable of vertical take-off and landing in confined areas. It is also capable of transition to horizontal high speed flight and is able to hover and loiter for a period of time. The vehicle includes coaxial forward and aft centerbodies, and a ducted rotor having a plurality of propellers. The ducted fan is aerodynamically efficient and is safe because of its unexposed rotor blades.
And since a UMD in accordance with the invention when operating in a ground mobility mode can walk on the terrain of the disaster site, however difficult the terrain, of prior art interest is the multi-legged walking robot disclosed e.g. by Takeuchi in U.S. Pat. No. 5,842,533. This device is capable of walking on uneven ground while carrying a payload. This multi-legged walking robot provides some of the basic capabilities for the ground mobility portion of a dual-mode UMD device in accordance with the invention.
In the six-legged walking robot described by Paynter in U.S. Pat. No. 5,040,626, each leg, composed of two links, has three controlled degrees-of-freedom of rotary motion. This device is also capable of walking on uneven ground and carrying a payload.
Obstacle avoidance and indoor navigation capability is needed in order to execute the mission of a robot scout in a disturbed environment. A system for obstacle avoidance and path planning is disclosed by Takenaka in U.S. Pat. No. 5,502,638. A survey of sensors and techniques appropriate for indoor positioning is set forth in Borenstein, J., et. al., xe2x80x9cMobile Robot Positioningxe2x80x94Sensors and Techniquesxe2x80x9d, The Journal of Robotic Systems, Vol. 14, No. 4, 1997, pp. 231-249, and in Borenstein, J., et. Al., xe2x80x9cNavigating Mobile Robots: Sensors and Techniquesxe2x80x9d, A. K. Peters Ltd., Wellesley, Mass., 1995.
Of prior art background interest regarding ducted fan VTOL devices, walking robots, distributed decentralized command and control of multiple mobile devices, as well as a unit for command control of mobile devices are the following U.S. patents:
U.S. Pat. No. 5,295,643 (1994)xe2x80x94ducted fan VTOL
U.S. Pat. No. 5,842,533 (1998)xe2x80x94legged robot
U.S. Pat. No. 5,040,626 (1991)xe2x80x94legged robot
U.S. Pat. No. 5,502,638 (1996)xe2x80x94path planning and obstacle avoidance
U.S. Pat. No. 5,340,056 (1994)xe2x80x94Active defense systemxe2x80x94cooperative
Operation of multiple UAVs (distributed-decentralized command and control of multiple unmanned devices).
Also of prior art interest in regard to various features included in a UMD robot scout in accordance with the invention are the following publications:
Chen, Chun-Hung et. al., xe2x80x9cMotion Planning of Walking Robots in Environments with Uncertaintyxe2x80x9d, Journal of Robotic Systems, John Wiley and Sons, Inc., Volume 16, No. 10, 1999, pp. 527-545.
Todd, D. J., xe2x80x9cWalking Machinesxe2x80x94An Introduction to Legged Robotsxe2x80x9d, Kogan Page Ltd., London U.K., 1985, pp. 63-168.
Movarec, Hans P., xe2x80x9cRobot Rover Visual Navigationxe2x80x9d, UMI Research Press, Ann Arbor, Mich., 1981, pp. 49-147.
Thorpe, Charles E., ed., xe2x80x9cVision and Navigationxe2x80x9d, Kluwer Academic Publishers, Norwell Mass., 1990, pp.
Robert, Luc, et. al., xe2x80x9cApplications of Non-Metric Vision to Some Visually Guided Robotic Tasksxe2x80x9d, in Aloimonos, Yiannis, ed., xe2x80x9cVisual Navigationxe2x80x94From Biological Systems to Unmanned Ground Vehiclesxe2x80x9d, Lawrence Erlbaum Associates Publishers, Mahwah, N.J., 1997, pp. 89-134.
Weng, J. J., et. al.,xe2x80x9cVisual Navigation Using Fast Content-Based Retrievalxe2x80x9d, in Aloimonos, Yiannis, ed., xe2x80x9cVisual Navigationxe2x80x94From Biological Systems to Unmanned Ground Vehiclesxe2x80x9d, Lawrence Erlbaum Associates Publishers, Mahwah, N.J., 1997, pp. 178-217.
Dean, Thomas, et. al., xe2x80x9cPlanning and Navigation in Stochastic Environmentsxe2x80x9d, in Aloimonos, Yiannis, ed., xe2x80x9cVisual Navigationxe2x80x94From Biological Systems to Unmanned Ground Vehiclesxe2x80x9d, Lawrence Erlbaum Associates Publishers, Mahwah, N.J., 1997, pp., 251-274.
Adams, Martin David, xe2x80x9cSensor Modeling, Design and Data Processing for Autonomous Navigationxe2x80x9d, World Scientific Publishers, Singapore, 1999, pp. 153-208.
Song, Shin-Min, et. al., xe2x80x9cMachines That Walkxe2x80x9d, The MIT Press, Cambridge, Mass., 1989, pp. 23-281.
Fahlstrom, Paul G., et. al., xe2x80x9cIntroduction to UAV Systemsxe2x80x9d, UAV Systems Inc., Columbia, Md., 1993, pp. II 42-II 47.
Kohlman, David L., xe2x80x9cIntroduction to V/STOL Airplanesxe2x80x9d, Iowa State University Press, Ames, Iowa, 1981.
Yavnai A., xe2x80x9cDistributed Decentralized Architecture for Autonomous Cooperative Operation of Multiple Agent Systemxe2x80x9d, in Proceedings of IEEE Symposium on Autonomous Underwater Vehicle Technology, Jul. 19-20, 1994, Cambridge, pp. 61-67.
Arlowe, H. D., xe2x80x9cAirborne Remote Operated Devicexe2x80x9d, Proceedings of the 15th Annual Technical Symposium of the Association of Unmanned Vehicle Systems, San-Diego, Calif., Jun. 6-8, 1988, pp. 1-13.
Borenstein, J., et. al., xe2x80x9cMobile Robot Positioningxe2x80x94Sensors and Techniquesxe2x80x9d, The Journal of Robotic Systems, Vol. 14, No. 4, 1997, pp. 231-249.
Borenstein, J., et. al., xe2x80x9cNavigating Mobile Robots: Sensors and Techniquesxe2x80x9d, A.K. Peters Ltd., Wellesley, Mass., 1995.
Even, S., xe2x80x9cGraph Algorithmsxe2x80x9d, Computer Science Press, Maryland, USA, 1979.
In view of the foregoing, the main object of this invention is to provide a remotely-controlled unmanned mobile device (UMD) adapted to function as a robot scout in behalf of a rescue mission to enter and reconnoiter the site of a disaster, to gather information regarding conditions prevailing at this site and to communicate this information to the mission which can then decide on rescue actions appropriate to the prevailing conditions. The UMD may be adapted to additional functions, all as required and appropriate.
More particularly an object of this invention is to provide a dual mobility UMD which is operable either in an air mobility mode or in a ground mobility mode, making it possible for the robot scout to fully explore the disaster site.
Among the significant advantages of a UMD robot scout according to the invention are the following:
A. The UMD can fly from a nearby safe station to the disaster area and reconnoiter the area to gather information regarding the conditions which prevail in the area, which information is conveyed to rescue mission personnel who are exposed to no risk in gathering the information.
B. When the UMD arrives at a disaster area, its on-board sensors then proceed to collect the information required by the rescue mission, which information is communicated to rescue mission personnel who are thereby advised of possible dangers they may encounter when entering the disaster area and can then take steps to avoid these dangers.
C. In its ground mobility mode, the UMD can traverse difficult terrain and walk through wrecked structures and ruins in order to reconnoiter the entire site.
D. When several UMD""s are enlisted by a rescue mission to reconnoiter a disaster area, they can communicate with each other to coordinate their activity.
E. The UMD is compact in form and light in weight, being composed mainly of miniature components.
F. The UMD should preferably be equipped with payload, which can be activated whenever required.
Briefly stated, these objects are accomplished in a remotely-controlled unmanned mobile device (UMD) adapted to function as a robot scout to enter and reconnoiter the site of a disaster and to communicate to a rescue mission information regarding conditions prevailing at the site, making it possible for the mission to decide on rescue measures appropriate to these conditions.
The UMD is operable in either of two modes. In its air-mobility mode, the UMD is able to vertically take off and land, to fly to the site and then hover thereover. In its ground-mobility mode, the UMD can walk on its legs over difficult terrain and through wrecked structures and ruins. The UMD is provided with condition-sensing detectors for gathering data regarding conditions prevailing at the site, and position-sensing sensors for avoiding obstacles in the path of the walking UMD, thereby assuring safe mobility. Other sensors govern geo-referenced navigational and flight control functions.